This invention relates to method of lamination and an apparatus comprising first and second laminating rollers defining a laminating gap therebetween and at least one gapping block positioned between the first and second rollers such that the gapping block determines and maintains a minimum gap width. The gapping block comprises a rigid gapping block body, which may be adjustable in width, and four or more load wheels rotatably attached to the gapping block body which ride on a portion of the first and second rollers.
U.S. Pat. No. 6,347,585 discloses a gap adjusting device for a rotary press comprising two rollers separated by an adjustable eccentric member.
U.S. Pat. No. 5,456,871 discloses a system for adjusting a calendaring gap which employs load measuring units and active feedback, typically mediated by a microprocessor.
U.S. Pat. App. Pub. No. US2002/0014509 A1 discloses a nipping roller gap adjusting device having a minimum gap setting means which includes an opposing pair of stops, one attached to a moving assembly that bears a roller and the other attached to the apparatus frame.
Briefly, the present invention provides an apparatus comprising first and second rollers defining a gap therebetween and at least one gapping block positioned between the first and second rollers such that the gapping block determines and maintains a minimum gap width. The gapping block comprises a rigid gapping block body and four or more load wheels rotatably attached to the gapping block body and is positioned between the first and second rollers such that at least two load wheels contact each roller. In a further embodiment, the width of the gapping block may be adjustable.
In another aspect, the present invention provides a method of laminating two or more sheet materials together by passing the sheets concurrently into a gap between a first roller and a second roller of a laminating apparatus, which apparatus additionally comprises at least one gapping block positioned between the first and second rollers such that the gapping block determines and maintains a minimum gap width.
In another aspect, the present invention provides a method of laminating two or more sheet materials together by passing the sheets concurrently into a gap between a first roller and a second roller of a laminating apparatus, which apparatus additionally comprises at least one gapping block positioned between the first and second rollers such that the gapping block determines and maintains a constant gap width which remains constant throughout the lamination.
In another aspect, the present invention provides an adjustable gapping block comprising: a first gapping block body element having two or more load wheels rotatably attached; a second gapping block body element having two or more load wheels rotatably attached, where the second gapping block body element is assembled with said first gapping block body element so as to allow linear motion of the two elements relative to each other in the direction of gapping block body width, and where at least one surface of either gapping block body element is canted with respect to a facing surface of the other gapping block body element when so assembled; a wedge disposed between the facing surfaces; and an adjusting screw to determine the position of the wedge between the facing surfaces, thereby determining the gapping block body width.
In this application, xe2x80x9cto laminatexe2x80x9d means to bond together two or more sheet materials.
It is an advantage of the present invention to provide a method of lamination which prevents damage to the continuous web during intermittent lamination of non-continuous sheets to a continuous web.